本研究对比了分离型和融入型形式聚焦教学时机对不同英语水平学习者语法习得的效果。126名初中生被分为分离组、融入组和控制组，每组学生又被分为高低水平组。所有学生完成错误改正题的前测、即时和延时后测。结果表明，两种时机对不同水平学习者都有促进作用，对高水平学习者效果更明显，分离型效果更好。对高水平学习者，分离型的即时和延时效果都好于融入型；对低水平学习者，两种时机的即时效果没有区别，但分离型延迟效果更好。

This study compared the effects of two kinds of timing of form-focused instruction (FFI) on learners’ grammar acquisition across different proficiency levels. Altogether 126 EFL students from a Chinese junior middle school were assigned to three groups: isolated FFI group, integrated FFI group and control group. All students from each class were further divided into high and low proficiency levels. All students finished pretest, immediate posttest and delayed posttest of an error correction test. The results showed that both isolated and integrated FFI had positive effects on learners, especially on those high-proficiency learners. On the whole, isolated FFI had advantages over integrated FFI. Specifically, isolated FFI produced better immediate and delayed effects on high-proficiency learners than integrated FFI. And for low proficiency learners, there was no significant difference between the immediate effects of the two kinds of timing, but the isolated FFI showed better delayed effect.